• Korean Journal of Optics and Photonics
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• v.5 no.2
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• pp.252-259
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• 1994

The method of calculating overlap dispersion caused by group velocity mismatch between uv and visible pulses in ultrafast pump-probe experiments is presented to discuss limitations of the time resolution and signal intensity. The calculations show arrangements using a single focusing lens shall result in undesirable time resolution and low signal intensity. Achromatic doublets result in unrealistic solutions. However, dramatic improvement in the time resolution and signal intensity is expected in the optical arrangements using separate lens for each pulse and in the arrangements using a cutoff secondary lens with a main lens. lens.

• Annual Conference on Human and Language Technology
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• 1990.11a
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• pp.104-111
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• 1990

대명사의 종류에 따른 대명사의 어휘적 특성이 대용어 참조해결에 미치는 효과를 살펴보기 위해서 두개의 실험을 수행하였다. 실험 1에서는 대명사 문장의 읽기시간과 선행어에 대한 어휘판단과제를 통해서 복수가 단수에 비해 읽기시간은 빠르지만, 어휘판단시간은 단수가 빠른 경향을 보였다. 그리고 단수는 애매성에 따라 반응시간의 차이를 보였다. 실험 2에서는 단수가 복수에 비해 어휘판단이 빠름을 반복하였다. 그리고 단수는 여전히 성별단서의 애매성에 대한 차이를 보였다. 이러한 결과는 대용어의 참조해결에 미치는 여러 요인 중에서 대명사의 어휘적 특성이 한 요인임을 증명하였다. 결론적으로 대명사의 종류에 따라 참조해결과정이 다르게 일어 날 가능성과 표상되는 글 모형도 달라질 수 있는 가능성을 제시하였다.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2010.05a
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• pp.18-24
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• 2010

ADHD 아동의 주의장애 원인이 반응 결정에서의 억제의 미숙인지, 전반적인 주의 기능의 미숙인지 알아보기 정상아동과 ADHD 아동을 대상으로 flanker 과제를 실시하였다. 실험 1 에서는 방해자극과 목표자극의 일치 (3: 일치, 불일치, 중립), 방해자극과 목표자극의 SO (3: -100, 0, 100 ms), 집단 (2; 정상, ADHD)의 3 요인 실험을 실시하였다. 정상아와 ADHD 아동간에 반응시간에서는 차이가 없었다. 그러나 정상아동에 비해 ADHD 아동이 부정확 반응을 더 많이 하였다. 특히 방해자극이 100 ms 먼저 제시되기 시작하는 SOA -100 ms 조건에서 두 집단의 차이가 크게 나타났다. 이 결과가 반응결정 단계에서의 억제에서 비롯되는 것인지 알아보기 위해 실험 2 에서는 목표자극의 반응 set(좌, 우)에 포함되지 않는 방해자극(상, 하로향함)을 제시하는 무관련조건을 추가하여 실험을 실시하였다. 실험 1 과 같이 불일치조건에서는 정상아동에 비해 ADHD 아동이 오반응을 더 많이 산출하였다. 그러나 무관련조건에서는 정상아와 ADHD 아동 간에 오반응에서 차이가 없었다. 즉 두 집단 모두에서 중립조건보다 무관련 조건에서 반응시간은 길었으나, 오반응에서는 차이가 없었다. 즉 정상아와 ADHD 아동 모두 전반적인 주의에서는 차이가 없다는 것을 시사하였다. 두 실험의 결과는 정상아에 비해 ADHD 아동이 반응 결정 단계에서의 억제에서 차이가 나는 것을 시사하는 것으로 해석되었다.

• Investigative Magnetic Resonance Imaging
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• v.11 no.1
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• pp.39-48
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• 2007

Purpose : To determine the diagnostic accuracy of four different sequences : moderately T2 weighted, two heavily T2-weighted single shot turbo spin-echo sequence and breath-hold axial-2D balanced turbo field-echo sequence(bFFE) for characterization of focal lesions. Materials and Methods : During the 3-month period between June and August 2005, seventy-six patients were proved to have ninety-three focal hepatic lesions on MR imaging. The patients consisted of 49 men and 27 women (age range, 15-75 years; mean age, 56.23 years). All MR images were acquired on a 1.5-T MR using the following sequences: 1. A breath-hold axial T2-weighted single shot turbo spin-echo sequence, 2. a breath-hold axial-2D balanced turbo field-echo sequence. Two radiologists performed quantitative analysis. Another radiologist measured the lesion-to-liver contrast-to-noise ratio at the region-of-interest in the four sequences. Results : There was no significant difference in inter-observer variability between the four sequences. The accuracy for both cyst and malignancy of moderate T2 weighted MRI (echo time: 80 msec) was also highest. There was significant difference for lesion characterization between moderate T2 weighted MRI and balanced steady state procession (p-value: 0.004) in the second reader. For longer echo time, the CNR of cystic lesions were markedly increased in comparison to lesions of other component. Conclusion : The accuracy and inter-observer variability of single shot turbo spin echo T2 weighted sequence was higher than bFFE. Although there was no statically significant difference, moderate T2 weighted MRI (echo time: 80 msec) was more accurate than heavily T2 weighted sequence (echo time: 300 msec). If the results for lesion characterization is equivocal in TE 80, the addition of heavily T2 weighted MRI (echo time: 180 msec) can be helpful.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.143-150
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• 2003

This study was performed to compare the effects of binding time(2hr, 4hr, 6hr and 16hr) and pressing condition (1kg, 3kg, 5kg and 10kg) on manufacturing restructured pork. Meat color, in terms of L, a, b showed no significant difference by treatment of binding time. Five kg pressing resulted in the highest red value(P<0.05). In tensile strength, 6 hour treatment showed significant difference ranging in 202.1g for raw restructured pork and 389.0g for cooked restructured pork. Five kg pressing showed the highest tensile strength, 114.6 for raw restructured pork and 303.3 for cooked restructured pork. In hardness, springiness, cohesiveness and chewiness, raw and cooked restructured pork showed insignificant difference regardless of pressing time. In sensory evaluation, four hour treated raw restructured pork showed the highest values of color, binding degree, shape, acceptance, while four or six hour treated restructured pork showed the highest values in cooked restructured pork. Therefore the optimal conditions for manufacturing restructured pork using TGase were four through six hour pressing with 5kg pressure.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.508-510
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• 2000

본 논문에서는 프레임 릴레이(Frame Relay : FR) 망과 ATM(Asynchronous Transfer Mode) 망이 연동할 때, 분석 대상인 연동장치(InterWorking Unit : IWU) 수신부에서 프레임이 처리되는데 걸리는 지연시간을 분석하였다. ATM과 FR 사이의 데이터 처리속도의 차이로 인하여 연동장치의 버퍼에서 프레임이 기다리게 된다. 이 때 지연시간을 IWU에서 ATM 망에서 들어오는 프레임의 평균값을 구한 다음에 Little's formula를 이용하여 수학적으로 분석하였다. 결과적으로 FR 연결된 수가 증가할수록 연동장치에서 프레임의 지연시간은 지수적으로 증가함을 알 수 있었다. 또한 지연시간을 분석하므로 해서 연동장치에서 timeout의 시간을 결정하여 프레임을 재전송할 수 있는 시간을 결정할 수 있었다.

• Korean journal of applied entomology
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• v.36 no.4
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• pp.299-310
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• 1997

A mutant, or(orange body), and the KNIH(Korea National Institute of Health) strain of the German cockroach, Blattella germanica(L.) (Orthoptera: Blattellidae), were observed continuously in semi-natural conditions through video taping and data processing by computers. Male adults were individually observed for 4-5 days in a rectangular-shaped rearing cage with four different microhabitats, allowing observations of behavior such as resting, feeding, drinking and communicating with other individuals. The frequencies of visits to and times spent within harborage were determined. Although there were relatively large variations among individuals, the average stays withing harborage ranged from 47-61% of the total observation time. The duration of within-harborage time was significantly different between maternal origins, while not distinctively different between the strains. Diel differences were observed in body strains. The time spent within harborage was longer in photophase than in scotophase. visiting frequency, which represented local activity around harborage, appeared slightly higher in the or strain than in the KNIH strain, and was significant in the or strain while it was not significant in the KNIH strain. Although there were variations among individuals, similar temporal patterns in some progenies from the same maternal origins were observed in time spent within harborage and in visiting frequency.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.4
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• pp.30-44
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• 2020

The application of PPLT is difficult to analyze and judge only from the effects of the delay time. In this study, the application of PPLT was proposed using not only the delay time of PLT and PPLT due to the change in traffic volume and the number of opposite straight lanes but also the traffic volume of passing a left turn and the number of conflict risks as indicators. According to the analysis, the more left-turn traffic than capacity and the less opposite-straight volume, the greater the PPLT effect. On the other hand, if the left-turn traffic is below capacity, the delay time will be reduced partially, but the overall passing left turn volume will not increase, and the conflict risk will increase. In addition, the conflict risk increases in the third lane or higher. Moreover, the difference of passing left-turn volume between PLT and PPLT showed a pattern similar to the delay time difference, and the PPLT coverage was wider than the difference in delay time and was associated more with the conflict risk numbers. Therefore, it would be reasonable to use passing left-turn traffic primarily, consider the delay time below the left-turn capacity, and consider the conflicting risk numbers simultaneously at or above the opposite straight three lanes.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.147-157
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• 2011

Purpose: The present study was conducted to investigate the actual condition of circle lens wear and the differences caused by the pigmentation in blinking rate, non-invasive tear break-up time (NIBUT), and lens surface between circle and soft contact lens wear during clinical application. Methods: Eighty subjects were surveyed to know the actual condition of wearing circle lens. Blink rate, NIBUT of 20 subjects in twenties were measured after separately wearing soft contact lens and circle lens for 5 days. Their lens surfaces were also observed by scanning electron microscope. Results: Fifty percent of circle lens wearers answered that major reason for changing circle lens was discomfort and 67% of answerers wore circle lens more than 6 hours a day. The tendency of increased blink rates in both wearers of circle and soft contact lens at 30 minutes later when tear film stabilized and 3 hour after lens wearing was shown on the 1st, 3rd and 5th day with expanding wearing time. Especially at 3 hours after lens wearing on the 3rd and 5th day, the difference of blink rates was statistically different in circle lens wear and soft contact lens wear. The NIBUTs of soft contact lens wearers and circle lens wearers were 6.0 and 3.7 secs, respectively, at 30 min later on 1st day and were significantly different. NIBUTs of soft contact lens wearers and circle lens wearers were also statistically different 3 hrs after lens wearing on the 1st day and the similar pattern of NIBUTs was shown on the 3rd and 5th day. The roughness of both surfaces in soft contact lens and front surface in circle lens was same. However, pigmented front surface of circle lens was rougher and uneven. Conclusions: As the results, the circle lens wearers might feel discomfort in clinical application since the difference in lens surface of circle lens would change lens wettability during wearing. The difference by tinting contact lens was shown from the result, which could help better wearing circle lens.

• Journal of Industrial Convergence
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• v.20 no.11
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• pp.157-164
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• 2022

This study attempted to understand the mediating effect of learning time in the effect of academic burnout on self-esteem of middle school students. To this end, a survey of 1,045 middle school students in Gyeongsangnam-do was conducted on academic burnout, learning time, and self-esteem. It was analyzed in four ways through questionnaire responses. First, as a result of analyzing the differences according to the collective characteristics of academic burnout, learning time, and self-esteem, there was no difference between groups, and self-esteem was significantly different by gender and grade. Second, as a result of correlation analysis, academic burnout and learning time showed a negative correlation with self-esteem, and learning time and self-esteem showed a positive correlation. Third, as a result of regression analysis, all learning times were partially mediated in the effect of academic burnout on self-esteem. This not only directly affects the self-esteem of middle school students, but also indirectly through learning time. Fourth, in the analysis by gender, it was confirmed that male students had no statistically significant effect on self-esteem, but female students had a significant statistical effect on self-esteem, so only female students had a partial mediating effect. As a result of the analysis by grade, the effect of learning time on self-esteem was significant in the 1st and 2nd graders of middle school, but the effect of learning time on self-esteem was not significant in the 3rd graders of middle school. Through the survey of this study, it was suggested that education and counseling should be conducted in the middle school period, which is a rapid growth period, considering that academic burnout has a different effect on learning time and self-esteem by grade as well as gender approach.